Evaluating the correlation between adrenal gland dimensions and aortic diameter in healthy dogs

In the present study, the relationship of normal adrenal dimensions with weight, aortic diameter, age and sex was evaluated. Moreover, a formula for estimating the normal dimensions of adrenal gland was provided. Thirty‐two intact adult dogs that were considered healthy based on history, physical examination, routine blood works and specific adrenal tests as well as absence of any abnormal ultrasonographic findings were included. Adrenal glands and abdominal aorta were imaged in the sagittal plane by ultrasound. Length, maximal height of the cranial and caudal poles, area and circumference of the left and right adrenal glands and also the internal diameter of the abdominal aorta were measured. Analysis showed that there is a positive correlation between the adrenal gland dimensions and weight and aortic diameter. The ratio of adrenal gland dimensions and the aortic diameter was calculated, but this ratio showed a great amount of variability in tandem with a significant correlation to the weight; Meaning that the ratio of the adrenal gland dimensions to the aortic diameter was not a reliable index for evaluating the size of the normal adrenal gland in animals with different weights. Therefore, we used the weight along with adrenal measurements in a linear regression model, and then, we were able to estimate the adrenal gland dimensions in different weights. Knowing the relationship of normal adrenal dimensions with the indices such as weight, age, sex and diameter of abdominal aorta can help the clinicians to diagnose the adrenal gland diseases.     

Effects of stocking density on oxidative stress status and mammary gland permeability in early lactating dairy cows

The current study was conducted to investigate the effect of stocking density (SD) on oxidative stress status and mammary gland permeability in early lactating dairy cows. Thirty‐two dairy cows were allocated into 16 blocks, basing on parity, previous milk yield, and body weight, and were then randomly assigned into one of the two treatments as follows: 75% (75SD) and 100% (100SD) SD. The cows were fed with same diet throughout the 8‐week experimental period. The milk yield and milk sample were collected on two consecutive days during the 8‐week experimental period weekly. Plasma samples were collected on fourth and eighth experimental weeks. Raw, energy‐corrected, and 4% fat‐corrected milk yield were significantly higher in 75SD‐cows than that of 100SD‐animals, respectively. The milk somatic cell count was lower in 75SD‐cows than that of 100SD‐animals. The levels of Na⁺, Na⁺/K⁺, bovine serum albumin and plasmin were lower in 75SD‐cows than those of 100SD‐cattle, respectively. The 75SD‐cows had reduced insulin and insulin/glucagon levels but higher prolactin and growth hormone concentrations, compared with those of 100SD‐animals, respectively. In conclusion, compared with low SD‐animals, early lactating cows with higher SD had higher oxidative stress status, which further led to a greater mammary gland permeability.     

转基因动物研究进展

转基因动物是现代生物技术中一个极其重要的研究领域，目前已经有转基因小鼠、兔、绵羊、山羊、猪、牛、鸡和鱼等多种转基因动物问世。本文综述了转基因动物的制作方法、转基因动物的应用研究以及所取得的重要成就，并指出了转基因动物存在的主要问题，展望了其发展前景。     

昌潍白猪内分泌腺的生长发育规律

系统研究了1～8月龄昌潍白猪(192头)内分泌腺的性状指标,并由此得出了其内分泌腺的生长发育规律及其与体重变化的回归方程.结果表明,肾上腺在1～3、5～6月龄生长速度最快(P＜0.01);甲状腺在1～8月龄有2个生长高峰期,即4月龄和6月龄;胸腺的生长高峰期集中于3～4月龄(P＜0.01),颈部胸腺在1～3月龄生长速度显著快于胸部胸腺,胸部胸腺左侧生长发育明显快于右侧;脑垂体在2～6月龄生长速度较快.肾上腺、甲状腺、胸腺、脑垂体随体重变化的回归方程分别是y=0.019 9x+0.801 6(r=0.975 9,P＜0.01);y=0.163 4x+1.286 8(r=0.976 1,P＜0.01);y=1.760 8x+26.995 0(r=0.946 2,P＜0.01);y=0.002 4x+0.062 0(r=0.908 3,P＜0.01).     

Mammary gland growth and vascularity at parturition and during lactation in primiparous ewes fed differing levels of selenium and nutritional plane during gestation

Background： Objectives were to examine the effects of selenium （Se） supply and maternal nutritional plane during gestation on mammary gland growth, cellular proliferation, and vascularity at parturition and d 20 of lactation. Rambouillet primiparous ewes （n = 84） were allocated to treatments in a 2 x 3 factorial. Factors were dietary Se （adequate Se [ASe, 11.5 μg/kg BW] or high Se [HSe, 77.0 μg/kg BVV]） and nutritional plane （60% IRES], 100% [CON], or 140% [EXC]）. At parturition, lambs were removed and 42 ewes （7/treatment） were necropsied. Remaining ewes were fed a common diet meeting requirements for lactation and mechanically milked twice daily until necropsy on d 20. At both necropsy periods, mammary glands were dissected and tissues harvested. Samples were analyzed for RNA, DNA, and protein content, cell proliferation, and vascularity. Where interactions were present （P 〈 0.05）, least squares means from the highest-order interaction are presented. Results： Final body weight of ewes was least （P 〈 0.002） in RES, intermediate for CON, and greatest for EXC, regardless of stage of the ewe at necropsy （parturition or d 20 of lactation）. In ewes necropsied at parturition, mammary glands were heavier （P = 0.02） in EXC compared to RES, with CON intermediate. Concentration of RNA （rag/g） was decreased （P= 0.01） in EXC compared to CON at parturition. There was a tendency （P= 0.07） for a Se by nutrition interaction in percentage of cells proliferating where ASe-EXC ewes had greater （P_〈 0.02） number of proliferating cells then all other treatments. Mammary vascular area tended （P = 0.08） to be affected by a Se by nutrition interaction where ASe-CON had less （P= 0.007） vascular area than HSe-CON ewes. In ewes necropsied at d 20 of lactation, the number of alveoli per area was decreased （P 〈- 0.05） in RES compared to CON and EXC-fed ewes. Conclusions： Results of this study indicate that proper maternal nutritional plane during gestation is important for mammary gland development, even out to d 20 of lactation.     

EVALUATION OF QUANTITATIVE THYROID SCINTIGRAPHY FOR DIAGNOSIS AND STAGING OF DISEASE SEVERITY IN CATS WITH HYPERTHYROIDISM: COMPARISON OF THE PERCENT THYROIDAL UPTAKE OF PERTECHNETATE TO THYROID‐TO‐SALIVARY RATIO AND THYROID‐TO‐BACKGROUND RATIOS

Thyroid scintigraphy is commonly used for evaluation of cats with hyperthyroidism, with the thyroid‐to‐salivary ratio (T/S) being the most common method to quantify the degree of thyroid activity and disease. Calculation of thyroid‐to‐background ratios (T/B) or percent thyroidal uptake of ^99mTcO^?₄ (TcTU) has only been reported in a few studies. The purpose of this prospective, cross‐sectional study was to evaluate a number of quantitative scintigraphic indices as diagnostic tests for hyperthyroidism, including the T/S, three different T/B, TcTU, and estimated thyroid volume. Of 524 cats referred to our clinic for evaluation of suspected hyperthyroidism, the diagnosis was confirmed (n = 504) or excluded (n = 20) based on results of a serum thyroid panel consisting of thyroxine (T₄), triiodothyronine (T₃), free T₄ (fT₄), and thyroid‐stimulating hormone (TSH) concentrations. In the hyperthyroid cats, median values for TcTU, T/S, and three T/B ratios were all significantly higher (P < 0.001) than values in euthyroid suspect cats or clinically normal cats. All scintigraphic parameters were relatively sensitive and specific as diagnostic tests for hyperthyroidism, but the T/S ratio had the highest test accuracy. The T/S ratio correlated strongly with the TcTU (r = 0.85). However, the TcTU had a higher and more significant correlation (P < 0.01) with serum T₄ (r = 0.76 vs. 0.64), T₃ (r = 0.77 vs. 0.64), and estimated thyroid volume (r = 0.62 vs. 0.38). Overall, calculation of TcTU is an accurate diagnostic test, but also appears to be the best parameter to predict the functional volume and metabolic activity of the feline adenomatous thyroid gland.     

父母代固始鸡食管的发育形态学研究

应用大体解剖学和组织切片技术,对0～25周龄父母代固始鸡的食管进行了发育形态学研究。结果表明,随着周龄的增加,食管的长度和质量大体呈增长趋势,食管长度与质量比值、食管指数都呈下降趋势。食管腺的纵径大体呈增长趋势,食管腺数目的规律表现不太明显。     

Diagnosis and treatment of mastitis in mares

Infection and inflammation of the udder (mastitis) is a common condition affecting all domestic mammals, but it appears to be less prevalent in mares than in dairy cows and dairy goats. The seemingly reduced incidence of mastitis in mares can be partially explained by the smaller size and relatively concealed location of the mare’s udder, coupled with a smaller storage capacity than cows and goats. Mastitis can affect lactating, peripartum, dry mares, mares at dry-off or prepubertal foals. Common clinical signs include swollen mammary tissue, abnormal mammary gland secretion, fever and anorexia; less common signs are hindlimb lameness and a swollen mammary vein. On rare occasions, mastitis pathogens can severely affect the nursing foal and mares may develop fibrotic tissue and consequent agalactia in the side(s) or quarter(s) affected. Based on the clinical presentation, mastitis can be classified as acute or chronic, and clinical or subclinical. Diagnosis is based on the clinical signs aided with aerobic culture and cytological evaluation of the gland secretion. In addition, these ancillary tests can also be used to assess prognosis and duration of treatment. Mares suffering from mastitis may present neutrophilia and hyperfibrinogenaemia. Treatment for mastitis includes antimicrobial therapy (systemic and/or locally), nonsteroidal anti-inflammatory drugs, frequent milking and cold hosing with/without hot-packing applied on the gland. While the frequent monitoring of mares after weaning and reducing food intake should be part of common practices at weaning, cleaning of the udder, control of insect populations and frequent milking of mares with a foal unable to nurse can also aid in preventing mastitis.